Session Announcement Protocol (SAP) is an experimental protocol for broadcasting multicast session information.
A SAP listening application can listen to the SAP multicast IP address and construct a guide of all advertised multicast sessions. SAP was published by the IETF as RFC 2974.
SAP typically uses Session Description Protocol as the format of the session descriptions. Announcement data is sent using IP multicast and User Datagram Protocol.
SAP includes provisions for authentication, encryption and compression.